3.1.1 periodicity

Question 1

how are elements arranged in the periodic table

Answer 1

by increasing atomic number

Question 2

why do elements in groups have similar physical and chemical properties

Answer 2

as they have the same electron configuration

Question 3

what is periodicity

Answer 3

a repeating pattern across different periods

Question 4

what is first ionisation energy

Answer 4

the amount of energy needed to remove one electron from each atom in one mole of gaseous atoms

Question 5

how are elements classified

Answer 5

S-block
D-block
P-block

Question 6

why are successive ionisation energies larger

Answer 6

-the ion formed is smaller than the atom
-there’s a greater proton:electron ratio so stronger nuclear attraction between ion and outer electron

Question 7

if there’s a large jump between the 2nd and 3rd ionisation energy which group is the element in

Answer 7

group 2

Question 8

which element has the largest first ionisation energies

Answer 8

Helium-it was one more proton than Hydrogen

Question 9

describe first ionisation energy down a group

Answer 9

-decreases
-atomic radius increases
-electron shielding increases
-nuclear attraction decreases
-easier to remove outermost electron

Question 10

describe first ionisation energy across a period

Answer 10

-increases
-more protons-increased nuclear attraction
-decreased atomic radius
-same shielding
-harder to remove outermost electron

Question 11

why is there a small drop from Mg to Al

Answer 11

Al outer electron is in the 3p sub-shell which is in a higher energy level than mg sub-shell in the 3s sub-shell

Question 12

why is there a small drop from P to S

Answer 12

P has electrons singly paired in the 3s sub-shell
-S has an electron pair in one of the 3s orbital which cause a repulsion which makes the second electron easier to move

Question 13

what is metallic bonding

Answer 13

strong electrostatic attraction between positively charged ions and delocalised electrons

Question 14

why does metallic bonding increase across a period

Answer 14

-ionic radius decreases
-more delocalised electrons
-more protons
-stronger electrostatic attraction between positive metal ions and delocalised electrons requires more energy to overcome

Question 15

describe diamonds structure

Answer 15

-each carbon atom is covalently bonded to 4 other carbon atoms
-high melting point
-hard
-cant conduct electricity
-wont dissolve in water

Question 16

describe graphite’s structure

Answer 16

-each carbon atom is covalently bonded to 3 other
-weak forces between the layers so sheets can slide over each other which makes graphite a good lubricant
-high melting point
-insoluble
can conduct electricity because of the delocalised electrons

Question 17

what is graphene

Answer 17

-2D layer of graphite-one layer

Question 18

what are the propeties of metals

Answer 18

-high melting and boiling point
-mallebale-metal ions can slide/move over eachother
-conduct electrcity-delocalised electrons can pass KE to eachother
-insoluble

Question 19

what types of forces are present as you go along the group